ライブラリ登録: Guest
8th Thermal and Fluids Engineering Conference (TFEC)
March, 26-29, 2023, College Park, MD, USA

FLOW AND HEAT TRANSFER FROM A HEATED CYLINDER MOVING ADJACENT TO WALL IN YIELD STRESS FLUIDS

Get access (open in a dialog) pages 1411-1421
DOI: 10.1615/TFEC2023.fnd.045894

要約

Cylindrical objects immersed in a uniform flow are frequently encountered in numerous industrial applications, namely, tubular heat exchangers, boilers, evaporators, mixing, polymer and food processing, filtration, etc. In addition to the strong influence of the inertial forces and rheological properties of fluids, the presence of solid boundaries has tendency to modify the flow and heat transfer characteristics in such flows. In the present numerical study, the flow of fluids with yield stress past a heated (isoflux) cylinder of diameter, d moving with the constant velocity adjacent to the adiabatic wall is investigated. The study covers the range of flow configurations from unconfined flow, gap ratio (Ξ gap between the wall and cylinder to the diameter of the cylinder), G = 100 to the lubricating flow, G = 0.01, over the parameter ranges, Reynold number (1 ≤ Re ≤ 40), Bingham number (0.01 ≤ Bn ≤ 100) and Prandtl number (1 ≤ Pr ≤ 100). The alteration of flow and temperature field has been visualized in terms of streamlines, yielded/unyielded regions, and isotherms. It is noticeable that the proximity of the wall plays a significant role in the modulation of yielded/unyielded regions in the vicinity of the moving cylinder. The gross parameters describing macroscopic fluid mechanical (drag coefficient, CD and the lift coefficient, CL) and thermal (average Nusselt number, Nu) behaviors are analyzed. The correlations for CD = ƒ (Bn, Re, G) and Nu = ƒ (Bn, Re, Pr, G) are proposed to facilitate their applications over the range of intermediate values.